title: The activity of synthetic leukotriene C-1 on guinea pig trachea and ileum.
abstract: The effects of synthetic leukotriene C-1 (LTC-1) on isolated guinea pig trachea and ileum have been determined and compared to histamine. LTC-1 produced a slow contraction of the trachea and the ileum with pD2 values of 8.7 +/- 0.1 (n = 14) and 8.5 +/- 0.1 (n = 13), respectively. In comparison, the pD2 values for histamine were 5.6 +/- 0.1 (n = 6) and 6.2 +/- 0.1 (n = 6), indicating LTC-1 was 2-3 orders of magnitude more potent. LTC-1 was antagonised by FPL 55712 with pA2 values of 6.9 +/- 0.1 (n = 5) and 6.4 +/- 0.1 (n = 7) on the trachea and ileum, respectively. Incubation with lipoxidase produced a time and enzyme dependent loss of biological activity and a concurrent shift in U.V. absorption spectrum.
mesh_terms: D000818:Animals; D001095:Arachidonic Acids / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002867:Chromones / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004987:Ethers / Q000494:pharmacology; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology; D007082:Ileum / Q000187:drug effects*; D008084:Lipoxygenase / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D014132:Trachea / Q000187:drug effects*
chemical_list: D001095:Arachidonic Acids; D002867:Chromones; D004987:Ethers; D006632:Histamine; C006312:FPL 55712; D008084:Lipoxygenase